Cumulative effect of gibberellic acid and phosphorus on crop productivity, biochemical activities and trigonelline production in Trigonella foenum-graecum L.

Fenugreek (Trigonella foenum-graecum L.) is an antidiabetic plant. Its bioactive compound, trigonelline, is known to counter diabetes through insulin secretion, modulation of β cell regeneration and quick activity of glucose metabolism related enzymes. A pot experiment was conducted in the natural conditions of net house of the Department of Botany, Aligarh Muslim University, Aligarh (UP), India, to evaluate the effect of four concentrations of GA3 (0, 10−7 M, 10−6 M and 10−5 M), alone and in combination with phosphorus (40 kg P ha−1), on growth, biochemical and yield attributes of fenugreek. Compared to control, the combination of GA3 and phosphorus (P40 + 10−6 M GA3) significantly increased the activities of nitrate reductase (30.8%) and carbonic anhydrase (30.7%) enzymes; it also enhanced the seed yield (140.6%) and the content of total chlorophyll (28.5%) and carotenoids (26%). There was also significant increase (19.51%) in the content of seed trigonelline.